Genesis Physics II rebuild and update...

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I had another thread going about crossover upgrades on these speakers, but now since I have finished with the upgrade, I figured I'd start a new thread dedicated to the Genesis II's and the process.

To make a long story short, I decided to preserve the original crossovers and terminal plates and go with all new components. New aluminum terminal plates and polished nickle binding posts replace the old. These were surface mounted on the rear instead of inside like the originals.

The original crossovers were glued to the back of the terminal plates and incorporated an attenuation switch for the tweeter which I kept bypassed. One speaker's crossover used a single 10uF poly cap and a large 2 ohm resistor. The other one used two 5uF electrolytic caps and a small 2 ohm resistor. Both used the same 22awg 0.47mH inductor.

The new, upgraded crossovers are made up of three capacitors to make up the 10uF needed. Known as "Cascade Bypass", I used a Dayton 1% Precision Audio 6.8uF cap, a Jantzen Z-Standard 2.2uF cap, a Jantzen Z-Superior 1.0uF cap, and a Jantzen 18awg 0.47mH inductor. I replaced all the internal 20awg wiring with quality OFC 16awg speaker wire. For mounting the crossover, I used Duct Seal. This stuff is excellent and I've used it a million times for such things as this. It not only isolates the components from vibration, but allows them to stick like glue to the enclosure's internal surface. Obviously, a horizontal flat spot is used. In this case, the bottom panel.


I've only had the system playing for about an hour at low volume, but from what I hear already, the bass is stronger, punchier and tighter and seems to have a little more detail. This is apparently from the larger cable alone since the woofer runs fullrange. Then again, the quality binding posts probably have something to do with it as well since those old spring terminals had seen better days.

Lower midrange appears to be just a tad more up front now. This might be due to the new arrangement of the fiberglass damping inside. When reinstalling the fiberglass, I created a nice direct "tunnel" of airflow straight to the PR. Upper midrange is highly detailed and neutral. The transition to the treble is completely seamless where that wonderful inverted dome tweeter takes over at a lofty 1.8kHz.

I believe I have read somewhere that those Jantzen caps I'm using take a while to properly break in. I have to say, even with an hour of running, they have opened up the upper midrange and treble noticeably. They're not brighter per say, but I can detect more detail in the music as well as a little more "air". The tweeters are still sweet and smooth which they are known for, but do seem to be a little bit more extended.


Now on to some pics...

Here they are in stock form.
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Yes, someone used a bunch of Gorilla Glue on this one and it was a PITA to remove.
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And that great tweeter that still gets plenty of praise today.
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Just as a quick update...

I have had the system running the entire weekend since Friday evening to run in the new caps along with a different amp. I pulled out the Baldwin tube amp to make room for a new amp I have coming. In the meantime, I'm using Dayton's version of the little Sonic T-amp. It doesn't sound too bad, but the top end seems a bit lacking and the bass is a bit softer. This is not due to the speaker mods because I had the tube amp playing for the first couple of hours Friday evening before switching it out.

Hopefully by the end of the week, my new amp will be here, the single ended, pure Class A, Monarchy Audio SM-70 Pro. :cool:
 
Listening to a song right now by Ray Charles and Norah Jones (Here We Go Again). There's a xylophone that's heard in the far right. It's so far right and genuine sounding, it scared me the first couple of times I heard it!

It sounded so real and lifelike that I got up and went into the kitchen looking for it, thinking that maybe my girlfriend left her iPhone in there and someone was texting her or something.

I never heard that before so I played that track again! I caught myself look over at the kitchen again one time. LOL! While listening closer this time around, I also noticed the B3 Hammond twirling and whizzing away to the near but yet still far left, directly along side my head. Ray and Norah clearly standing about two feet in front of the speakers and about at normal standing height.

All of this with the cheap Dayton DTA-1 T-amp. Man, I can't wait to get the Monarchy Audio amp in the chain.

Not that anyone on here gives a hoot... :(
 
I I replaced all the internal 20awg wiring with quality OFC 16awg speaker wire.

OFC = oxygen free copper, I assume. Is this legitimate? What are supposed to be the benefits of this type of wire? How do you produce OFC?

Now and then, I hear about OFC and am just curious what it is all about.

Some time ago I spoke to a former employee of the Genesis company. He currently supplies replacement drivers for I guess at least some of the Genesis
line. See Human Speakers

Regards,
Pete
 
OFC = oxygen free copper, I assume. Is this legitimate? What are supposed to be the benefits of this type of wire? How do you produce OFC?

Now and then, I hear about OFC and am just curious what it is all about.

Some time ago I spoke to a former employee of the Genesis company. He currently supplies replacement drivers for I guess at least some of the Genesis
line. See Human Speakers

Regards,
Pete

No oxidation on the copper I guess, hence lower resistance maybe? I never really looked into it actually.

I'm well aware of the "Human" site and all the drivers and components Huw offers. However, I decided to go the route I did because I didn't care for the new/replacement speaker terminal panels, binding posts and crossovers that he supplies. I'm also a little upset that after two emails to him, I never received a response which I find odd as everyone else says that he responds rather quickly.

As good as these speakers sounded in their stock state, I wanted to make sure I put the best components possible that I could afford, or at least willing to put into them. I'm already hearing a vast improvement over the original, more ways that one.
 
Here is an informative website discussing speaker wire in general and the oxygen-free-copper type, OCf

In essence, using good quality copper wire is needed, but reducing the oxygen content of copper wire beyond what it usually is doesn't improve anything in audio applications.

-Pete
 
Nice rebuild thread and good clear pictures. Nice to have a good pair of Genesis speakers ready for another 20 years.

Has anyone seen the cat lately?

David S.

Thanks David! Yeah, these II's will be good for quite a while now. And the kitty escaped to safety before the "woofer" came home. :p


Here is an informative website discussing speaker wire in general and the oxygen-free-copper type, OCf

In essence, using good quality copper wire is needed, but reducing the oxygen content of copper wire beyond what it usually is doesn't improve anything in audio applications.

-Pete

Well if you noticed, I'm just using my own DIY "White Lightening" speaker wire from the amp to the speakers. To me, wire is wire. As long as it's big enough, it'll work just fine. I don't get into all of that marketing stuff.

As for the whole "OFC" thing, I just figured it meant that it wouldn't oxidize so easily or quickly.
 
As for the whole "OFC" thing, I just figured it meant that it wouldn't oxidize so easily or quickly.

This sounds right. Oxygen free and wire size is pretty much the only selection criteria I've ever used.

I do have some old apature 10 gauge wire that I was offered at a 90% discount from a buddy that runs a stereo shop because an error was made in manufacturing and it was terribly oxidized. I've had speakers connected with it though and even though it's as green as the statue of liberty, it still seems to function just fine.
 
This sounds right. Oxygen free and wire size is pretty much the only selection criteria I've ever used.

I do have some old apature 10 gauge wire that I was offered at a 90% discount from a buddy that runs a stereo shop because an error was made in manufacturing and it was terribly oxidized. I've had speakers connected with it though and even though it's as green as the statue of liberty, it still seems to function just fine.

Yeah, for the longest time I used some old original 12awg Monster Cable that my oldest brother had from the early 80's. That stuff was totally green from one end to the other. I just used a knife and scraped off the green on either end and used it for a long time. Later on, I got a job and bought brand spankin' new "original" 12awg Monster Cable... Absolutely no difference in sound.

However, I always enjoyed the smell of new speaker cable and how it filled the room of that fresh rubber smell. :D
 
update info

Hi Charles
very nice job! I have the same speakers from the 80' and I want to make the same update (I need to refoam them for the 2nd time), could you please tell me if you have done further adjustments or improvements? where is possible to buy online the crossover/plate parts?
any other suggestions?
thanks
best regards
Dario
 
Isn't that Howard's product the greatest? If the finish needs more than just some rehydration, they also make the wonderful Restor-a-Finish series in range of colours.

It is. The enclosures are actually in pretty great shape. I was thinking of using some #0000 steel wool and Restor-A-Finish, and possibly finishing off with some low gloss Tung oil. But I think that might be a bit much that these speakers really don't need.

As it is, throughout this past week, the wood has seemed to take on a slightly darker shade just from applying those two coats of Feed & Wax.

I may hit them another time or two with the Feed & Wax in the next couple of weeks or so, just for the heck of it, since it looks like they had never been treated since new in 1979.

Here's a quick before and after shot. They've seemed to darken up a touch since.

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